RISK Indoor Air Quality model

This page provides a description and a link to a "RISK Indoor Air Quality model" modeling tool that can be used for modeling exposure levels or information needed in exposure assessment.

Short description

The latest published version of the RISK computer model is designed to allow calculation of individual exposure to indoor air pollutants from sources. The model runs in the MS-Windows operating environment and is designed to calculate exposure due to individual, as opposed to population, activity patterns and source use. The model also provides the capability to calculate risk due to the calculated exposure

Link

http://www.epa.gov/appcdwww/iemb/risk.htm

Long description

The Indoor Environment Management Branch has developed an IAQ model for analyzing the impact of sources, sinks, ventilation, and air cleaners on indoor air quality. Early versions of the model allowed calculation of indoor concentrations as a function of time. The model incorporates the latest results from EPA research on sources, sinks, ventilation, and air cleaners. The model predictions have been compared with results of test house experiments and the agreement between model predictions and experiment have been very good. The latest published version of the computer model, called RISK, is designed to allow calculation of individual exposure to indoor air pollutants from sources. The model is designed to calculate exposure due to individual, as opposed to population, activity patterns, and source use. The model also provides the capability to calculate risk due to the calculated exposure. Risk is calculated using a risk calculation framework developed by Naugle and Pierson (Naugle, D.F., and T.K. Pierson. A framework for risk characterization of environmental pollutants. Journal of Air and Waste Management Association, Vol.41, P. 1298. 1991.).

The model uses data on source emissions, room-to-room air flows, air exchange with the outdoors, and indoor sinks to predict concentration/time profiles for all rooms. The concentration/time profiles are then combined with individual activity patterns to estimate exposure. The model allows analysis of the effects of air cleaners located in either/or both the central air circulating system or individual rooms on IAQ and exposure. The model allows simulation of a wide range of sources including long-term steady-state sources, on/off sources, and decaying sources. Several sources are allowed in each room. The model allows the analysis of the effects of sinks and sink reemissions on IAQ.

The model has recently been revised to allow improved analysis of particulate matter and multiple pollutants.

The results of test house experiments are compared with model predictions. The agreement between predicted concentration/time profiles and the test-house data is good. The model is designed to run in the MS-Windows operating environment.

Key words

indoor air, modeling, human health, time use, exposure